Mask



FIG. 1 is a perspective view a mask showing our new design;

FIG. 2 is another perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a right side view thereof, with the left side being a mirror image thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken line showing of the headgear in FIG. 1 depicts environmental structure and forms no part of the claimed design. The broken lines shown adjacent to the solid lines in FIGS. 2 and 5-7 define the bounds of the claimed design and form no part thereof. 

CLAIM The ornamental design for a mask, as shown and described. 